Rao Dinesh, Murray John V, Beegle Richard D, Patel Jeet, Raymond Mallory J, Breen Joseph T, Sandhu Johnny, Rhyner Patricia A
Mayo Clinic, Jacksonville, United States.
Neuroradiology. 2025 Nov 7. doi: 10.1007/s00234-025-03820-w.
Imaging findings of otosclerosis have been previously described using traditional energy integrated detector CT scanners. Recent developments in photon counting detector CT allow improved spatial and contrast resolution over previous technology.
A retrospective observational case series review was carried out in 53 patients (106 temporal bones) who had imaging findings of otosclerosis. Imaging findings of otosclerosis were documented, including specific plaque location, the presence of otic capsule expansion, and IAC diverticula. The Symons and Fanning classification was used to categorize findings. The presence of the cochlear cleft was documented. 50 asymptomatic patients were reviewed to determine the presence of features that could be confounded for otosclerosis.
Per the Symons and Fanning classification, the following types were found in individual temporal bones: type 0-13, type 1-48, type 2a - 12, type 2b - 6, type 2c - 16, type 3-4. Seven patients had imaging findings that did not fit the classification criteria, primarily isolated otospongiotic plaques in other parts of the otic capsule. The fissula ante fenestram was involved in 91 otosclerosis and 4 temporal bones in asymptomatic patients. The cochlear cleft was visible in 3 otosclerotic and 10 normal temporal bones. Otic capsule thickness in symptomatic patients: concave - 52, flat - 27, convex - 24. In asymptomatic patients: concave - 98, flat - 2, convex - 0. IAC diverticula: present in 36% of otosclerosis and 2% of normal. Isolated foci of otospongiosis were identified in several patients without classic fenestral or retrofenestral disease.
Photon counting CT allows excellent visualization of otospongiotic plaques. Due to the high resolution, subclinical findings can be overlooked in asymptomatic patients and plaque may be visualized in the otic capsule that are not part of existing classification systems. The current study coincides with previous studies which demonstrate that otosclerosis may occur in any part of the otic capsule.
耳硬化症的影像学表现此前已通过传统的能量积分探测器CT扫描仪进行描述。光子计数探测器CT的最新进展使得其在空间和对比分辨率方面优于先前技术。
对53例（106块颞骨）有耳硬化症影像学表现的患者进行回顾性观察病例系列研究。记录耳硬化症的影像学表现，包括特定斑块位置、耳囊扩张情况以及内听道憩室。采用西蒙斯和范宁分类法对结果进行分类。记录蜗窗裂的情况。对50例无症状患者进行检查，以确定可能与耳硬化症混淆的特征。
根据西蒙斯和范宁分类法，在各颞骨中发现以下类型：0型-13块，1型-48块，2a型-12块，2b型-6块，2c型-16块，3型-4块。7例患者的影像学表现不符合分类标准，主要是在耳囊其他部位出现孤立的耳海绵化斑块。窗前裂在91例耳硬化症患者和4例无症状患者的颞骨中出现。在3例耳硬化症和10例正常颞骨中可见蜗窗裂。有症状患者的耳囊厚度：凹面-52，平面-27，凸面-24。无症状患者：凹面-98，平面-2，凸面-0。内听道憩室：在36%的耳硬化症患者中存在，在2%的正常患者中存在。在一些没有典型窗前或窗后疾病的患者中发现了孤立的耳海绵化病灶。
光子计数CT能很好地显示耳海绵化斑块。由于分辨率高，无症状患者的亚临床表现可能被忽视，且在耳囊内可显示出不属于现有分类系统的斑块。本研究与先前研究一致，表明耳硬化症可能发生在耳囊的任何部位。
